Means for pouring metal in the formation of cast-iron pipe



J. R. McWANE. MEANS FOR POURING METAL IN THE FORMATION OF CAST IRON PIPE.

APPLICATION FILED MAR.23,1920- Patented Aug. 2, 1921..

INVENTOR WITNESSES PATENT OFFICE.

UNITED STATES JAMES R. McwANE, or BIRMINGHAM, ALABAMA.

MEANS son rouam METAL In THE roRmA'rIoN'or cAs'r-mon PIPE.

Specification of Letters Patent.

Patented Aug. 2,1921.

Application filed March 23, 1920. Serial No. 368,170.

.To all whom it may concern Be it known that I, JAMES R. MCWANE, a citizen of the United States, residing at Birmingham, in the county of Jefferson and State of Alabama, have invented a new and useful Means for Pouring Metal in the Formation of Cast-Iron Pipe, of which the following is a specification.

This invention has reference to machines for the centrifugal casting of iron pipe and the like, and its object is to provide a ma-v chine or apparatus whereby sensibly uniform casting may be obtained. p

In accOrdance with the invention, the machine includes head and tail stocks capable of receiving, supporting and rotating a suitable mold into which molten material, which may be specifically considered as molten iron, is received, and the mold with the contained iron rotated, to cause the molten iron to flow to the inner walls of the mold and be there held by centrifugal force until the iron has chilled sufliciently in conformity with the mold to hold its shape.

It has been heretofore proposed to produce castings centrifugally and to produce iron pipe by centrifugal casting, but the difficulties presented have been such as to prevent any but short lengths of pipe from being produced.

In accordance with American and English practice, iron pipe is made in standard lengths of twelve feet to sixteen feet, but heretofore the difiiculties encountered have precluded the successful formation of such pipes by centrifugal casting, although the showing in the' drawings, but may b changed and modified so long as such changes and modifications mark no material departure from the salient features of the use of such centrifu-' the invention as expressed in the appended claims.

In the drawings,

Figure 1 is an elevation of a centrifugal casting apparatus with means for pouring the metal in accordance with the invention.

Fig. 2 is a plan view of the structure shown in Fig. 1, omitting some parts.

Flg. 3 is a detail of a stop used in connection with the ladle.

Referring to the drawings, there is shown a support or bed 1 of any suitable construction, with which uprights 2, 3. areassociated at respectively opposite ends, The upright 2 carries at its upper end a rockable ladle Land the upright 3 similarly carries a rockable ladle5. The ladle 4: is provided with trunnions 6 supported in journal bearings on the upright '2 and the ladle 5 is provided with trunnions 7 carried by journal bearings on the upper end of the upright 3.

Mounted on the bed or support'l at the I end with which the upright 2 is associated is a head stockS, and at the end associated with the upright 3 is a tail stock 9. The head and tail stock structures may be similar to and have'functions like those of lathe head and tailstocks, the purpose being to receive and support a pipe mold 10, in which the casting of the pipe is to be performed. Since the pipe to be made in the mold is of considerable length, which length as hashereinb-efore been stated is twelve feet to sixteen feet standard, the apparatus is correspondingly large. In an installation for the production of pipe on a commercial scale, track rails 11 are provided for the support of the molds in approaching the castingm'achines and in moving away therefrom, such arrangement facilitating the handling of the molds.

The head stock 8 may be considered as adjustable'along the support 1 by suitable means and the tail stock may also be adjustable along the support 1, but as such adjustability does not enter into the present invention, it need not be particularly shown and described. Adjacent to the head stock is a carriage 12 and adjacent to thetail stock is a carriage 13. The carriage 12 is 'movahle lengthwise of the bed lvby the hand-wheel 14 and a rack 15. The carriage 13 is moved lengthwise of the bed l by a hand-wheel '16 anda rack 17 A pulley 18 on the tail stock may betaken as representative of any suitable means for the rotation of the mold 10. The carriage 12 carries a pouring gate 19 and the caror pulley 21, and fast to one of the trunso that the ladle 4 may be rocked for a distance before the slack is taken up, after which the ladle 5 will participate in the movement of the ladle 4. Furthermore, the sheave 22 is smaller than the sheave 21, say

about half the diameter, so that the full rocking movement of the ladle 5, in pouring, may take place after the ladle 4 has poured about half its charge, and the ladle 5 may be emptied while the ladle 4 still contains a small portion of its charge, the remnant of the charge of the ladle 4 representing about the amount of metal which it takes to fill the bell end of the pipe mold beyond the diameter of the body of the pipe.

In the installed apparatus, molten metal is carried to the ladles 4 and-5 by a much larger ladle 26, which latter may be carried by a suitable crane (not shown 1n the drawings).

It has heretofore been found to be practically impossible to cast pipe by the centrifugal process if thepipe was longer than a small fractional portion of the length of standard cast iron pipe; that is, when the pipe is as much as twelve feet or sixteen feet in length.- This has been found to be due to the introduction of'the molten metal into one end of the mold because the metal, in flowing towardthe other end of the mold, becomes more or less cooled and therefore dull .and sluggish. Moreover the metal has a tendency to flow toward the farther end and rebound in the form of .a wave which is noticeable in the metal, even after the mold 155 .has been rotated and. the metal is driven come by excessive speed of revolution. Furthermore, the wave formation tends to carry the loose sand of the mold and impurities in the iron into a circumscribed area where such impurities become fixed on cooling and the pipe is torrespondingly weakened.

Surging of the molten metal, due to pouring the charge into one end of the mold, is minimized by this invention by pouring the charge intoboth ends of the mold but not simultaneously. The charge fromthe ladle 4 is started into the bell end of the mold until about half the contents of the ladle 4 is discharged. By this time the slack of the cable 24 is taken up and continued tilting of the ladle 4' causes a tilting of the ladle 5 in a direction to pour its contents into the funnel 20. As the tilting of the ladle 4 progresses, the ladle 5 tilts but with considerably greater rapidity so that by the time the ladle 4 approaches but has not yet reached the fully discharged position the ladle 5 has completed the discharge of its contents.-

The molten metal initially poured from the ladle 4 enters the mold 10 at the bell end thereof, this being the end corresponding to the bell end of the completed pipe, and the molten metal flows toward the opposite end of the mold considerably beyond the middle thereof. During this movement of the molten metal, more or less debris is carried along at the head of the flow and the forward end of the flow becomes more or less dull and sluggish. As soon, however, as the flow from the second ladle begins, the second batch of metal progresses along the pipe mold toward the bell end of the mold and meets and livens up the first flow of molten iron so thatlwhen the pouring is completed the tendency to surgingis counteracted and the iron in the mold is of very nearly uniform temperature throughout. If the iron from the two ladles were poured in simultaneously at both ends of the mold, the dull iron would go to the center from each ladle, causing at this point an excess of sluggish metal and impurities and therefore resulting in weakness.

When the mold begins to revolve, the tendency of the molten metal is to flow away from the axis of rotation and this tendency is more pronounced as the distance from the axlsof rotation increases. The result of this is that the mass of metal in the mold immediately adjacent to the bell end is robbed to fill the bell end to an extent causing a. thinning of the walls of the forming pipe. Therefore, after the retion has been commenced, the remainder of the metal in the ladle 4 is oured into the mold, thus supplyinga su cient quantity of molten metal to make up for the amount.

volving of the mold to cause centrifugal acremoved centrifugallyfrom the immediate nei hborhood of the bell end of the pipe.

11 order to automatically determinethe amount of metal to be. retained in the ladle 4, there is provided a stop 27 mounted to rock on the bar 28 carried by the upright 2 in the path of the ladle 4. The arm 27 is through one gate,

rovided with a counterweight 29 tending I to urge it toward the ladle 4 so that when the counterweight29 has normally in its path.

a stop pin 30, which pin is carried by the upright 2 in such manner as to be readily removed therefrom, thus allowing the stop 27 to move farther in'the direction of pouring movement of the ladle 4. This additional movement of the ladle results in the discharge of the metal retained in the ladle, but as the ladle 5 is at this time already emptied, further tilting has no effect upon it.

While the pouringof the metal into the mold may be performed by two operatives each stationed at a respective ladle, the attempt to maintain a certain timed between the pouring movements, by one operative being guided by the other, is uncertain in results. With the structure of this invention, a single operative controlling the handle 23 is able to. cause the pouring to occur in predetermined order with certainty of results and with greater rapidity than could be done where the manipulation of the two ladles depended upon unrestricted movement of independent operatives.

What is claimed is r 1. In the casting of iron pipe and the like centrifugally' in rotatable molds having pouring gates at opposite ends, connected mechanical means for. introducing molten metal into the mold through both gates simultaneously.

2. In the casting of iron pipe or the like centrifugally in rotatable molds having pouring gates at opposite ends, means for introducing molten metal into the mold and means for then introducing molten metal into the mold through both gates simultaneously, said means at the opposite ends of the mold being timed to complete the introduction of the molten metal at the second named end of the mold prior to the completion of the introduction of the molten metal at the first named end of the mold.

3. In the casting of iron pipe and the like oentrifugally in rotatable molds having pouring gates at opposite ends, means for introducing a predetermined amount of molten metal into one end of the mold, means for then introducing a predetermined amount of molten metal into the other end of the mold, and means for introducing additional molten metal into the first named end of the mold until the full amount of molten metal desired has been deposited in both ends of the mold.

4. In the casting of iron pipe and the like centrifugally in rotatable molds having pouring gates at opposite ends, means for introducing a determined amount of molten relations end of the mold metal into one end of the mold through the pouring gate thereat, means timed with relation to the first named means for then pouring molten metal into the other end of the mold through the pouring gate thereat with the pouring continuing at both ends of the mold .until the full determined amount has been deposited in the second named end of the mold, and means whereby the pouring is continued into the first named end of the mold subsequent to the completion-of the ouring at the second named end of the mold until the mold has received its full charge.

5. In the casting of iron pipe and the like centrifugally, means forpouring molten metal into rotatable molds having pouring gates at opposite .ends, comprising a ladle at each tiltable to deposit the molten metal into respective gates, and connections between the tiltable ladles provided with lost motion parts whereby the tilting of one ladle will cause the tilting of the other ladle after the tilting of the first ladle has progressed for a predetermined time.

6. In the casting ofiron pipe and the like centrifugally, means for pouring molten metal into rotatable-molds having pouring gates at opposite ends, comprising tiltable ladles in operative relationeach to a respective gate, and lost motion connections between the ladles having a predetermined amount of slack whereby the tilting' of one ladle causes the tilting of the second ladle after the tilting of the first ladle has progressed to a predetermined extent.

7. In the casting of iron pipe and the like centrifugally, means for pouring molten metal into rotatable molds having pouring gates at opposite ends, comprising tiltable ladles for molten metal each associated with a respective gate, and slack flexible connecthe adjacent gate before the second ladle is moved to pouring position.

8. In the casting of iron pipe and the like centrifugally, means for pouring molten metal into rotatable molds having pouring gates at opposite ends, comprising tiltable ladles for molten metal each associated with a respective gate, and slack flexible connections between the ladles for causing the rocking movement in the other ladle, the slack bein enough to permit'one ladle to rock suf-' fic1ently to pour about half its contents into the ad a'cent gate before the second ladle is moved to pouringposition, and the second ladle havin means to which the connections are attached and proportioned to cause the rocking of the second ladle -to the fully of one ladle to produce a rocking poured position before the first ladle reaches the, fully poured position.

- 9, In the casting of iron pipe and the like centrifugally, means for pouring molten.

metal into rotatable molds having pouring gates at opposite ends, comprising rockable ladles at respective ends of the mold, means whereby one ladle may 'be tipped toward the pouring position, means for causing the second ladle to tip toward the pourin position after the first has partly comp eted its pouring, with both ladles then continuing the pouring movement until the second ladle is empty and the first ladle has com-- pleted the greater portion. of its movement, and means for permitting the then the other ladle toward 'pouring'posi-.

come empt completion of the ouring movementof the first ladle "after t e second ladle has bea g g 10. In t e casting of iron pipe and the like centrifugally, means for pouring molten metal into rotatable molds having pouring gates at opposite .ends, comprising two rockable ladles at respectively b'pposlte ends of the'mold, means for tipping first one and tion in predetermined order, with the movement of the ladles then simultaneous for a portion of their travel until the second ladle is empty, means for .stopping the movement of the first ladle near the completion of its pourin movement to holdback a por-' first ladle may andmeans wherebythe released to complete its pourin movement,

11. n the casting of iron pipeand the tion of its 0 era,

' i like centrifugallyigmean's for pouring molten metal into rotata 1e molds having pouring ates at opposite ends, comprising rockable adles individual to the respective gates and ofa combined capacity suflicient for the mold, and connections between the ladles for causing them to move in succession for a portion of their pouring travel and then simultaneousl with the second ladle completing its pour1n before the first ladle.

12. In t e casting of iron pipe and the like centrifugally, means for pouringmolten I metal into rotatable molds having pouring curing ing a normal slackw gates at o positeends comprising rockable ladles 'indi vid ual to the respective gates and of a combined capacity sufiicient for the mold, and'connections betweenthe ladles for causing them to. move in succession for a portion of their pouring travel and then si-- multaneously, with the second ladle, com pleting its pouring before the first ladle, and

the first ladle havlng means whereby a part.

of its contents may be withheld and-subsequently' poured into themold to complete the pouring operation.

13. In the casting of iron pipe and the like centrifugally, means for pouring molten metal into rotatable molds having pouring. gates ,at opposite ends, comprising rockable ladles individual and adjacent to the-gates, v with the ladles of a combined capacity corresponding to that of the mold, sheaves on the respective ladles with one sheave of eater diameter tharf? the other, and a [cab e connectlng' the sheaves and having a normal slack-whereby on rotating the larger sheave -pa'city corresponding to that ofthemold, I

sheaves on the respective ladles 'with one sheave of greater diameter than the other, and acable connecting the sheaves and hav erebyon rotating the largersheave the smaller sheave will be actuated after the slack in the cable i's'taken up and the first ladle has been rocked for a predetermined distance, the sheaves being proportioned to cause a-more rapidmovement of the second ,ladle than ofthefirst ladle. In testimony thatI claim the foregoi'ng'as my own, Ihave hereto afiixed my. signature.'

-- 'JAMES R. MewAN'E'. 

